Champ made a crucial par save on the par-5 18th hole at TPC Twin Cities, to finish the day with five birdies and no bogeys on his card.

At 15-under 269, Champ beat Venezuela's Jhonattan Vegas (68) and South Africans Louis Oosthuizen (66) and Charl Schwartzel (68) by two strokes.

Keith Mitchell shot a final-round 67 to take fifth place at 12 under.

Cam Davis carded a scintillating seven-under 64 to soar 39 spots and finish the highest-placed Australian in a tie for 28th.

"Coming down the stretch I felt very calm, very relaxed and kind of in my zone." - Cameron Champ.

Cameron Percy (67, 6 under) was a shot adrift of Davis while and Aaron Baddeley slid down the field with a 74 leaving him 3 under.

On another hot day in Blaine, Minnesota, Champ was far from his physical best.

He felt some dizziness along the back nine, putting his hands on his knees at one point as he hung his head to try to regain some composure.

"Coming down the stretch I felt very calm, very relaxed and kind of in my zone," Champ said.

"Obviously 18 made it a little interesting. I felt like I hit a great second shot from where that lie was, and obviously hit a great approach there into about two feet and made the putt."

After winning tournaments in each of the past two seasons, Champ was having a poor campaign before arriving at TPC Twin Cities.

He had missed more cuts (11) than he'd made (10) entering the event and was on the outside of the FedExCup Playoffs looking in.

Champ's third PGA Tour win was projected to vault him up the FedExCup standings from 142nd place to 49th.

Playing six pairs ahead of Champ, Oosthuizen followed up his third-place finish at last week's Open Championship by tying for second – his fifth top-three finish of the calendar year without a win.

He shot in the 60s for all four rounds, saving his lowest score for Sunday, when he sank seven birdies to counteract two bogeys.

"I was happy to play this week," Oosthuizen said.

"I sort of didn't really want to just think about last week, about not playing great on that Sunday and immediately quickly go back into tournament mode and then play this tournament."

The PGA Tour is off next week for the men's golf event at the Tokyo Olympics.